1. Field of the Invention
The present invention relates to a construction machine such as a hydraulic shovel, and, more specifically, to a device removing/re-inserting structure and a device removing/re-inserting method for removing/re-inserting a fuel tank in a device installation space, between a floor plate and a bottom plate of an upper frame of a swivel upper structure in a construction machine.
2. Description of the Background Art
Based on FIG. 10, the background art will be described by taking a small-size hydraulic shovel as an example. A similar structure is disclosed in JP 2008-240676A.
This hydraulic shovel comprises: a crawler-type base carrier 1; a swivel upper structure 2 mounted on the base carrier 1 rotatably about an axis vertical to the ground; and a working attachment A comprised of a boom 3, a non-illustrated arm, a non-illustrated bucket, and boom, arm and bucket cylinders (only the boom cylinder 4 is illustrated) and mounted to the swivel upper structure.
The swivel upper structure 2 has an upper frame 5 to which various devices such as an engine, a guard panel 6 covering the devices, and a cabin 8 provided with a cab seat 7, are mounted. The upper frame 5 has a bottom plate 9, and the devices are installed in a device installation space S defined between the upper frame bottom plate 9 and a floor plate 10 by a plurality of pillars, in an installation position for the cabin 8 (left-front region thereof).
The following description will be made on an assumption that a fuel tank 11 made of a synthetic resin is installed in the device installation space S which is provided with a pair of front and rear pillars each provided on right and left sides, i.e., four pillars in total (in FIG. 10, only left-front and left-rear pillars 12, 13 are illustrated). Each of the pillars has a lower end and an upper end fixedly attached, respectively, to the upper frame bottom plate 9 and the floor plate 10. The fuel tank 11 is installed removably with respect to the device installation space S in a horizontal (rightward-leftward) direction in order to perform internal washing or the like, and a left opening of the device installation space S serves as an insertion/removal port for the fuel tank.
As used in this specification, the terms “front”, “rear”, “right” and “left” mean directions as seen from an operator seated in the cab seat 7 within the cabin 8.
In the left-front and left-rear pillars 12, 13 located on the side of the insertion/removal port, the left-rear pillar 13 supporting a left-rear portion of the floor plate 10 is originally located in a tank removal/re-insertion path, so that it hinders an operation of removing and re-inserting the fuel tank 11.
Therefore, heretofore, as illustrated in FIG. 10, the left-rear pillar 13 has been mounted to be offset rearwardly with respect to the fuel tank 11 so as not to hinder the tank removal/re-insertion operation, and an upper end thereof for supporting the floor plate 10 has been formed in an inverted L shape overhanging frontwardly to a position suited to support the floor plate 10. As above, the left-rear pillar 13 is positionally constrained, and the upper end thereof has to be overhung, which brings disadvantages in terms of strength.
In view of the above circumferences, an object of the present invention is to provide a device removing/re-inserting structure and a device removing/re-inserting method for a construction machine, which enable to remove or re-insert a device in a device installation space, while disposing a pillar that obstructs a removal/re-insertion of the device at a position most suitable for functioning as the pillar and with a structure most advantageous in terms of the strength, in a condition that the device required to be removed/re-inserted in the device installation space from the outside is installed in the device installation space, between a lower member (in the above example, the upper frame bottom plate), and an upper member (in the above example, the floor plate), and at least one of the pillars defining the device installation space is the demountable pillar in the removal/re-insertion of the device.